For decades it has been conventional to employ stepped free-wheel cog adapters that threaded onto the rear hubs of multispeed bicycles. Because the external surfaces of such cog adapters were stepped, the cogs had to have two different internal diameters, one internal diameter for the larger-diameter region of the cog body and a smaller internal diameter for the smaller region thereof. Because of this, and in order to achieve desired combinations of cogs, it was sometimes necessary for the bicyclist to have two different (for example) "number 17" cogs, and other cogs, one with one internal diameter and another with a different internal diameter.
In the mid-1980s, a company started to sell a "free hub" or cassette, having a single external diameter. Thus, all of the cogs could have the same internal diameter and it was possible to achieve various combinations of cogs without the necessity of having two of any particular cog (or cogs).
The above-indicated hub assemblies are conventionally of the pawl and ratchet type, which type generated the common clicking noise of the rear hubs of bicycles. Attempts have been made to achieve hubs having no such clicking noise, and having other benefits. This was and is done by employing pin-type roller clutches. However, and especially for cassettes or free hubs, the external diameters of which are the same throughout, and are relatively small, such pin-type roller clutches do not generate sufficient torque for certain important applications. Stated otherwise, they are insufficiently strong for such applications.